1. Field of the Invention
This disclosure is related to semiconductor devices.
2. Description of the Related Art
A routing switch in a field programmable gate array (FPGA) acts as a switch that decides a connection between two logic blocks (LB), or between an LB and an input/output (I/O) circuit. The routing switch holds information of the connection in a configuration memory that connects to a pass gate (a pass transistor).
Recently, FPGAs using oxide semiconductors as channel layers of transistors are proposed (Patent Documents 1 and 2). The oxide-semiconductor-based FPGAs have advantages in reducing power consumption and downsizing. Further, a multi-context FPGA that have more than one configuration are proposed (Non Patent Document 1).